If the biomes were meant to represent the outdoors in as beautiful a way as was possible aboard ship, then the central core was a study in contrast. While it wasn’t exactly ugly, it was definitely oriented toward the functional.

There was no artificial gravity in the core. The tram continued to work by virtue of having the tracks sunken into the “walls” and gripping the frames of the tram cars above and behind the wheels with magnets just enough to keep the cars and passengers (who were advised to hold on) from floating off into the interior.

The inner space was a wide open tube, and actually was pretty usable as a recreation area. As long as one was careful to avoid colliding with passing trams or other passengers and crew, flying in zero-g was—or would have been, rather—encouraged as a recreational activity. View ports to either side of the tram provided views “down” onto the biomes far below them. From the tracks and looking up, they could see the biome on the opposite side of the ship, a sight both comforting and somewhat disconcerting. It would look almost like they were orbiting a world if it weren’t for the features being a bit too close and distinct.

The tunnel they’d taken had come up the biome’s side nearest the bridge; the main computer lab was closer to the engines, at the other end of the ship. The trams were considerably faster than walking or running, but it would still take them a good hour to cross to the other side.

“Make sure you hang on,” Cobb said to them all, “or at least make sure that if you go flying off, you’ll reach a bulkhead instead of goin’ parallel to the tracks. It’s a long way across and nobody’s set up the catcher lines!”

Catcher lines were a safety feature, rubbery elastic cables that were supposed to be strung within the core so that anybody who lost their direction—which happened often, even to experienced spacers—could catch themselves instead of drifting for hours. Of course on a fully populated ship someone was likely to notice them and catch them, but under the circumstances, they didn’t have that assurance.

Everyone kept a firm grip on the car frames after that. They passed the time filling pvt. Pixton in on what they’d seen and learned so far. She was astonished at the huge amount of overgrowth in the rain forest biome. “That sounds wonderful! I could use a few hours at the beach,” she said wistfully. “Maybe a few days …”

“We don’t have time to laze around like civvies,” Cobb growled from the last car. Dann, startled, looked back at him. They were only halfway to the far end, and he looked impatient.

“I didn’t mean—” Pixton started.

“It’s okay, pvt. Pixton,” Rose said. The two were seated together in the middle car. “We know what you meant. It’s fine, and once we’re sure everything’s working the way it should, there are very good reasons for you to spend time recuperating after being frozen for 500 years.” She said the last with a pointed look at Cobb.

“Cobb is really starting to piss me off,” Jackson said in a low voice pitched just for Dann, and maybe for Rose’s android hearing. “If he doesn’t lay off soon …”

“Maybe he needs a way to let off steam,” Dann replied, just as low-voiced.